The gaseous species concentration of Jet A-1, GTL, CTL and a blend of 80 vol.% GTL and 20 vol.% hexanol jet fuels in laminar coflow diffusion flames have been measured and studied. These species are carbon monoxide, carbon dioxide, oxygen, methane, ethane, ethylene, propylene, and acetylene. Benzene and propyne concentrations were also detected in CTL flames. 1-Butene has been quantified for the blend of GTL and hexanol flame. The detailed experimental setup has been described and results from different flames are compared. The CO is produced in a same amount in all the flames. The CTL flame had the largest and GTL/hexanol flame had lowest CO2 concentrations. The results indicate that GTL and GTL hexanol blend flames produce similar concentrations for all the measured hydrocarbon species and have the highest concentration among all the jet fuels. The experimental results from Jet A-1 fuel are also compared with numerical studies by Saffaripour et al.

The gaseous species concentration of Jet A-1, GTL, CTL and a blend of 80 vol.% GTL and 20 vol.% hexanol jet fuels in laminar coflow diffusion flames have been measured and studied. These species are carbon monoxide, carbon dioxide, oxygen, methane, ethane, ethylene, propylene, and acetylene. Benzene and propyne concentrations were also detected in CTL flames. 1-Butene has been quantified for the blend of GTL and hexanol flame. The detailed experimental setup has been described and results from different flames are compared. The CO is produced in a same amount in all the flames. The CTL flame had the largest and GTL/hexanol flame had lowest CO2 concentrations. The results indicate that GTL and GTL hexanol blend flames produce similar concentrations for all the measured hydrocarbon species and have the highest concentration among all the jet fuels. The experimental results from Jet A-1 fuel are also compared with numerical studies by Saffaripour et al.

Surrogate fuels are mixtures of pure hydrocarbons that mimic specific properties of a real fuel. The use of a small number of pure compounds in their formulation ensures that chemical composition is well controlled, helping increase reproducibility of experiments and reduce the computational cost associated with numerical modeling. In this work, surrogate mixtures were developed for Jet A fuel based on correlations between fuel properties (cetane number, smoke point, threshold sooting index (TSI), density, viscosity, boiling point and freezing point) and the nuclear magnetic resonance (NMR) spectra of the fuel as a measure of the fuel's chemical composition. Comparison of the chemical composition and target fuel properties of the surrogate fuels developed in this work to a Jet A fuel sample and other surrogate fuels proposed in the literature revealed the superiority of these surrogate fuels in mimicking the fuel properties of interest.

No description available.

No description available.

In order to find politically feasible ways to reduce greenhouse gas emission emissions, governments must examine how policies affect a variety of stakeholders. The costs and benefits of low carbon technology options are unique and affect different market participants in different ways. In this thesis, we examine the cost effectiveness of carbon mitigation technologies and policies from the social perspective and from the perspective of consumers. In Chapter 2, we perform an engineering-economic analysis of hybridizing concentrating solar thermal power with fossil fuel. We examine the cost effectiveness of substituting the solar power for new coal or gas and find the cost of mitigation to be approximately ~$130/tCO2 to ~$300/tCO2. In Chapter 3, we quantify some externalized social costs and benefits of wind energy. We estimate the costs due to variability and transmission unique to wind to have an expected value of ~$20/MWh. In Chapter 4, we quantify the cost effectiveness of a renewable portfolio standard and a carbon price from the perspective of consumers in restructured markets. We find that both that the RPS can be more cost effective than a carbon price for consumers under certain circumstances: continued excess supply of capacity, retention of nuclear generators, and high natural gas prices. In Chapter 5, we examine the implications of lowering electricity sector CO2 emissions in PJM through a Low Carbon Capacity Standard (LCCS). We estimate that an LCCS would supply the same amount of energy (105,000 GWh) as the RPS’s in PJM and an additional ~10 GW of capacity. We find that the LCCS could be more cost effective for consumers than an RPS if it lowered capacity prices.

As algae-derived biofuel is a promising renewable energy source, it is well-established that micro-algae have the potential to make a significant contribution to transportation fuel demand. Although it has many advantages including high areal productivity, there are many negative factors. One of these factors is the predation of algae by amoebas, protozoans, ciliates and rotifers, particularly in open pond systems. For example, the rotifer Brachionus plicatilis, is able to eat as much as 12,000 algae cells per hour and can be responsible for an entire pond crash within days. Thus, these higher organisms need to be controlled in order to satisfy large-scale algae crop and biofuel production demand. One method of predation control involves the introduction of a toxic chemical to an algal culture that the predator has a higher sensitivity to with respect to algae. Ideally, predation could be minimized or eliminated without a substantial effect on the algal culture growth. Chlorella kessleri was used as the algal culture and Brachionus calyciflorus as the source of predation. Research was conducted in five stages. First, chlorine dissipation tests were carried out using spring water, distilled water, Bolds Basal Medium (BBM), and three different dry weights of algal suspension in order to analyze the dissipation rate of the residual chlorine. The results showed that chlorine in distilled water and spring water rarely dissipated while chlorine concentration in algal suspension rapidly decreased by a maximum of 90% within the second hour. Second, acute chlorine toxicity tests were conducted in order to find the 24-hr LC50 of B. calyciflorus. The 24-hr LC50 of the test animal was 0.198 mg Cl/L. Third, chlorine toxicity tests were conducted in order to find the LC50 of Chlorella kessleri. The 24-hr LC50 of C. kessleri was 0.321 mg Cl/L. Based on these results, the test animal was more sensitive to chlorine than the test algae; therefore chlorine may be used to avoid algae pond crashes by B. calyciflorus. Fourth, C. kessleri and B. calyciflorus were combined into one test to determine how long it would take to observe an algal culture crash. The result demonstrated that the higher the population of predators in algal suspension, the faster it crashed. Finally, chlorine, C. kessleri, and B. calyciflorus were combined into one test to determine what chlorine concentration and dosing interval was needed to significantly reduce predation without significantly reducing algae growth. The results of the fifth experiment showed that the effective intermittent chlorine concentration was between 0.45 and 0.60 mg Cl/L, and a short interval of chlorine dosing was effective in inhibiting rotifers in algal suspension. Even though the rotifers in algal suspension were inhibited by 0.45 to 0.60 mg Cl/L, algae growth was greatly inhibited by chlorine. In this respect, future work is needed to reduce the effect on algae by chlorine or alternative chemicals.

This thesis develops the notion of the bioenergy transition as the long-term transformation of biomass from a local resource into a global commodity. An historical assessment is combined with interdisciplinary analysis that focuses especially on liquid biofuels and highlights the environmentally innovative case of bioethanol. The bioenergy transition is investigated from several different perspectives: technical-economic, socio-economic, socio-technical and political-economic. Linkages across different levels from household to global are analysed in relation to the effectiveness of bioenergy policies. In addition to studies at household and national levels, a North-South perspective is taken by including two major regions: the European Union (EU) and the Southern African Development Community (SADC). The relation of EU biofuels policy to international climate and trade regimes is assessed to show how regional-global linkages affect policy design and implementation. Household bioenergy markets in developing countries are poorly articulated and difficult to link to other sectors; a detailed choice model in Ethiopia showed that product-specific factors should be evaluated to inform design of programmes and policies. Municipal and sub-national markets for bioenergy have been successfully linked to national policies to coordinate supply and demand in Brazil and Sweden. Regional market development for biofuels has great potential in southern Africa but regional-national linkages currently remain unexploited. National level efforts remain quite important in terms of energy security and environmental innovation, as evidenced in Brazil, Malawi and Sweden. Biofuels sustainability criteria in the EU Renewable Energy Directive (EU-RED) were evaluated in relation to the international climate and trade regimes and were found to shift some costs onto developing countries. One of the mechanisms for assuring biofuels sustainability is bilateral agreements, which remain untested but potentially effective. Cross-level linkages were often unexploited in the cases studied; national approaches cannot easily capture complementarities across sectors and scales in biophysical and economic terms. Linking biofuels markets across different levels from household to global through regional development policies and specialised governance mechanisms could help to steer the bioenergy transition towards sustainability. / <p>QC 20141112</p>

As biofuels were growing in importance, Jatropha curcas has been widely promoted as the best suitable source for biodiesel that can be exploited by developing countries .Whilst there were fears that this development may threaten food security and put a strain on other natural resources there was a view that if well managed, the activity may spur rural economic growth thereby reducing poverty and unemployment. The purpose of this study was to investigate the impact that growing Jatropha curcas for supplying the biodiesel industry has made on the livelihoods of the households that were involved within the community of Mpaka in Swaziland. The target respondents were all the farmers that had an agreement with D1 Oils Swaziland and actually planted Jatropha curcas based on the Sustainable Livelihoods framework and using qualitative techniques data were collected using documentation, semi-structured interviews, focus group discussion, and some observation. Content analysis was then carried out to document the history of growing Jatropha curcas in Swaziland; map out the vulnerability context for the community of Mpaka; identify the range of assets that create the different livelihood strategies for the different households; determine the effect of policies and institutional conditions; and describe what the stakeholder’s view of growing Jatropha curcas is. The findings of the study revealed that growing Jatropha curcas greatly reduced the households’ vulnerability to drought, crops being browsed by livestock and high cost of farming inputs. However the study also revealed that the activity did not yield the desired outcome of income generation as the project did not continue due to bad publicity coupled with a poor policy environment and lack of coordination between and within government ministries and departments. Whilst it can be concluded that that the activity had a negative impact on the households involved it showed a great potential provided government through the relevant ministries and departments creates an enabling environment of proper policies and institutions and by involving all stakeholders at the right time. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Nickel aluminate reduced in hydrogen for 3 h at 500ºC was studied for desulfurization of model fuel comprised of dodecane spiked with benzothiophene (300 ppmw S). The nanopowder adsorbent was synthesized using combustion chemical vapor condensation, which created nickel aluminate with a BET specific surface area of 57.8 m2/g and average particle size of 11.7 nm. The nickel aluminate adsorbent removed 23 µmol of sulfur gram at breakthrough (<15 ppmw S). Regeneration by further heat treatment in hydrogen or air recovered 25% and 40% of original capacity, respectively.